Here is a zip file with the addon. There are really only 3 files other than the libs: "Config.lua", "Squire2.lua" and "Localization.lua".

The pre-hooking UIErrorsFrame_OnEvent is suspicious. The right implementation is to replace UIErrorsFrame's OnEvent handler, not to prehook the function. There's a little mod called pError that's an example of the right way to do it. Or if all the mod is trying to do is suppress error messages, you can unregister and reregister the event: